[Updated Mar. 2] — Microsoft's lawsuit against Linux devicemaker TomTom is “clearly a provocation,” and the action will ultimately make the open source community stronger. So said Keith Bergelt, CEO of the Open Invention Network (OIN), in a brief interview with LinuxDevices a day after the suit came to light.

Bergelt said, “The OIN, Software Freedom Law Center, and the Linux Foundation are unified in our view that it is an act of provocation. The people concerned about patent issues around open source are firmly allied and prepared to support TomTom.”

Bergelt added, “The community has matured well beyond the days of SCO. Look at the reaction then, versus now. Today, we understand that patent suits are part of life, whether they come from a troll, or from a troll within a multi-billion dollar organization like Microsoft.”

Bergelt seemed confident that the open community has little to worry about from the new suit over this patent. He said, “These patents are fairly well-understood. Now, they've been the subject of re-examination, and people feel comfortable they can get up to speed quickly.”

The suit

As reported yesterday, Microsoft sued devicemaker TomTom for five alleged infringements in userspace software. The suit also alleged three infringements theoretically capable of involving the Linux kernel. Two involve Microsoft's “Joliet” extensions for long filenames in FAT (patents 5,579,517 and 5,758,352), while the other involves wear-leveling technologies enabling the deployment of FAT on flash filesystems (patent 6,256,642).

Microsoft recently lost a case in Germany involving its two Joliet patents. However, to Bergelt's knowledge, Microsoft has not recently been asserting its wear-leveling patent. OIN is fairly aware of what Bergelt called Microsoft's “daily, covert” patent assertions, thanks to its “Linux Defenders 911” program offering legal referrals to open source users.

A history of non-enforcement?

Microsoft for decades has apparently seen it in its own best interests to allow the proliferation of FAT as a kind of lingua franca filesystem. FAT first became ubiquitous on floppy disks, even those used by Mac OS computers, by Unix systems, and basically every operating system. Microsoft did not complain very loudly, if at all.

As flash memory began replacing floppy disks, FAT made the obvious transition to USB keys and SD cards, such as those in the TomTom devices that enable users to transfer map data between their PCs and their in-car nav systems. Unlike floppies, Flash can only be written to in large, page-sized chunks, and each page can tolerate only a finite number of write cycles (typically about 100K in the cheapest parts). Patent 6,256,642 appears to describe one “wear-leveling” scheme aimed at distributing the writes over the entire flash part, to maximize longevity.

Flash can be attached to devices through a number of different interfaces. Some, like SD and CF and other removable storage media interfaces, use hardware (a low-powered, pre-programmed microcontroller) to make the flash appear to the host operating system as if it were a block device (like a floppy disk or IDE drive). A block filesystem like FAT can then be created and used atop the flash, with the MCU transparently handling wear-leveling. It's important to note that Linux plays no part in the wear-leveling here, which is all done by the SD or CF microcontroller.

Flash can also be attached via a simpler NOR memory interface (called “MTD” in the Linux kernel). This approach sometimes requires binary-only Linux drivers that do wear-leveling, because (as evidenced by Microsoft's patent on it), wear-leveling is often a sensitive area for IP law.

However, some recent NAND memory products that connect via a NOR interface are able to use open source drivers, thanks to programmed microcontrollers on the actual flash parts that again handle all the IP-sensitive processing in hardware. Such an architecture enabled flash pioneer M-Systems to open drivers in 2006 for some of its DiskOnChip parts. In general, moving sensitive IP out of the Linux kernel and into the firmware layer is the approach long recommended by open source advocates like Bruce Perens.

We're not sure about the exact architecture of TomTom's products, but we're puzzled why they might have been singled out by Microsoft. As a product company, they probably purchased a storage product and selected wear-leveling technologies with a long history of use in lots of similar products produced by other consumer electronics products.

As for the use of FAT and Joliet in consumer devices, well… basically every consumer electronics device with removable media uses these “patented” technologies, and Microsoft is going to have a mighty uphill battle enforcing patents it has obviously been convenient for the company to ignore for decades.

Bergelt has a different theory on why Microsoft decided to sue TomTom over FAT and wear-leveling. Not because they have a real case, but to take advantage of an opportunity.

Opportunism at work?

Bergelt pointed to rumors that Microsoft tried to acquire TomTom in 2006. He noted that TomTom has used both embedded Linux and embedded Windows in its products. And, he pieced together a history as follows, “Assertions are year-long, or two years long. Maybe Microsoft wanted to buy TomTom, but they didn't want to sell. So they started asserting patents, hoping to encourage them to at least only license Microsoft operating systems. That didn't work, so they sued.”

And why now? Bergelt points to a Reuters story suggesting that in the current tough economic climate, TomTom is “out of conformity” with a loan agreement. He said, “It is not beneath a monopolist to put all these pieces together and look to take advantage of a situation.”

Microsoft launched its own NavReady software stack for PNDs last summer.

Bergelt added, “Who knows the real motivations. But it seems a thoughtless and provocative act, whether by design or not. But in time, it will only prove to make sure the community is ready to do what's necessary under any situation.”